Bullmastiff Weight Chart
Expected adult weight, growth by age and a calculator for your Bullmastiff puppy. AKC weight: males 110 to 130 lb (50 to 59 kg), females 100 to 120 lb (45 to 54 kg).
- Male, AKC
- 110 to 130 lb (50 to 59 kg)
- Female, AKC
- 100 to 120 lb (45 to 54 kg)
- Growth-chart size class
- Above 40 kg
Predict your Bullmastiff puppy's adult weight
Enter your puppy's age and weight to see an estimate.
Not veterinary advice. PuppySizer gives estimates from published sources. It cannot examine your pet. For any health concern, ask your own veterinarian. Read the full disclaimer.
Growth chart not available
A Bullmastiff is above 40 kg (88 lb) as an adult. The published veterinary growth charts stop at 40 kg: the authors found giant breeds too variable to model. Rather than draw a curve we cannot back up, this page gives only the breed weight. Ask your vet to weigh your puppy at each visit and plot it on a breed-specific chart.
Bullmastiff size questions
How big does a Bullmastiff get?
The American Kennel Club gives 110 to 130 lb (50 to 59 kg) for males and 100 to 120 lb (45 to 54 kg) for females. Individual dogs can fall outside a breed range, and a mix or a dog from working lines may be larger or smaller.
Is there a growth chart for Bullmastiff puppies?
Not here. A Bullmastiff is above 40 kg (88 lb), the limit of the published growth charts, and the chart authors could not build a reliable curve for giant breeds. Your vet can track your puppy against a breed-specific chart.
Other breeds in the same size class
Sources
- AKC breed pages (weight line only). American Kennel Club. Read 2026-11-08. Used for: Breed weight ranges, as numbers only. No AKC text is reproduced.
- Growth standard charts for monitoring bodyweight in dogs of different sizes. Salt C, Morris PJ, Wilson D, Lund EM, German AJ. PLoS ONE 12(9): e0182064 (CC BY 4.0). Read 2026-11-08. Used for: Centile growth curves for five size classes (adult weight under 40 kg) from 12 weeks to 2 years, built from Banfield Pet Hospital records. We read the values off the published charts.
AKC weight read on 2026-11-08 from akc.org/dog-breeds/bullmastiff (numbers only). Facts last checked November 8, 2026.